Psychologist William Szlemko of Colorado State University has been studying the aggressive-driving tendencies of those who personalize their cars with stickers, vanity plates, etc., and he claims that his study shows that the more personalized "territorial markers" on a car, the more aggressive its driver is likely to be. One experiment involves ignoring a green light at an intersection and timing the amount of time it takes the driver behind to blast the horn; according to Szlemko, drivers of vehicles with "markers" (which we assume includes Truck Nutz and Safety Cats) go for the horn a full two seconds faster than marker-free vehicles. [Washington Post]

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